PURPOSE: To control exposure by the output from a signal accumulation type sensor having plural picture elements by providing means for emitting the signal corresponding to the max. picture element information outputted from said sensor, the signal corresponding to the sum total of the picture element information and the signal corresponding to accumulation time and means for calculating these signals.
CONSTITUTION: The sensor unit 7 starts accumulating each picture element signal and a switch 28 turns on during the outputting of a signal ST to reset a capacitor 27 when a sensor driving circuit 20 outputs the signal ST. The switch 25 is turned off by a signal ED and the capacitor 27 stops the accumulation. The potential VIT proportional to the accumulation time of the unit 7 is obtd. in this stage. A peak holding circuit 21 detects the max. value from the output of each picture element and generates the voltage VPH proportional thereto. An adder circuit 22 calculates the sum total of the output and generates a voltage VAD. The voltage VAV corresponding to the set aperture value is emitted in a signal line EX from a variable resistor 33 and a multiplier and divider 29 outputs the information VOP necessary for controlling the shutter from a terminal OP according to the equation. Here K is a constant of proportion.
AKASHI AKIRA
OTAKA KEIJI
SUDA YASUO
HIRAMATSU AKIRA
